720p24pn: TCMODE locked in DF mode - not NDF

From what I understand, if you are set to 720p24pn, you can only record in Non Drop Frame - NDF. It will be blue and unchangeable. I am attempting to sync the timecode of two HVX200s via firewire, and they are both set to 720p24pn. So their TCMODE should both be locked on NDF. One of them is locked on DF (drop frame) mode. I need to shoot in the morning with synced timecode! Anybody know why one cam is locked in DF at 720p24pn? Shouldn't this be impossible? A solution by the morning would save me from having to manually sync multiple cameras in editing with over 50 hours of footage to be shot over the next week! Thanks so much for any ideas!